Delayed cut-off for gas burners



R. D. SMITH.

DELAYED CUT-OFF FOR GAS BURNERS. APPLICATION man JULY 24. ms. RENEWEDSEPT. 30. 1921.

Patented May 9, 1922 stares RAYMOND D. SMITH, 015 BOSTON, MASSACHUSETTS,ASSIGNGR TO SHAWIVIUT MACHINE 'W'ORKS, ENG, A CORPOB-ATIQN OF'MAIITE. I

CUT-OFF Application filed July 24:, 1918, Serial No. 110,851

To all whom a may concern:

Be it known that I, RAYMOND D. SMITH, a citizen of the United States,residing at Boston, in the county Sulfoll: and State of Massachusetts,have invented certain new and useful Improvements in Delayed Cut-' Offsfor Gas Burners, of which the follow ing is a full and completedescription.

My present invention relates to new and useful improvements inautomatically delayed cut-offs for illuminating gas burners of the openflame type, particularly of the form hereinafter described.

The type of automatic cut-off that I preferably employ is similar tothat described in my co-pending application Serial No. 110,950,thepresent improvement concerning principally the application of this typeof cut-off to a flame protected, turn-down burner of the open flame orfish-tail type, so called.

I have illustrated my invention herein, in a form of gas burner havingin combination with the main valve and burner stem a small capacityby-pass conducting around the valve and into the stem, and having apilot flame projecting cage or lantern chamher that, in normal ope"ation of the main burner, is lowered or retracted from the ori tics ofsaid burner, such cage or chamber being cylindrical, and alsosymmetrically disposed about and vertically slidable on the burner stem.

In applying my above-mentioned automatic cut-off to this type of burner,I have provided a composite burner and valve structure that possessesnovel advantages in that, through a single, self-contained illuminatingburner unit, full light may be had for leaving the premises afteractuation of the valve controllingagencies for causing a delayedautomatic .tiirn-down of the main burner flame, the smaller main burnerflame or pilot light being left constantly burning after such automaticturn-down to uide subsequent approach to the burner for turning up thelight.

In the compact and simple burner and valve arrangement herein disclosed,the heretofore mentioned slidingcage is necessarily interposed in part,between the main burner orifice and the orifice of an auxiliary burnerthat comprises part of the cut-off governing agencies. Accordingly, aspecific object of the present invention is so to arrange theSpeoitcation of Letters Patent.

en GAS ,BURNEE$- Patented May 9, 1922..

. B enewed September 30, 19 21 Serial No. 504,492.

relative disposition of this cage and said auxiliary burner thatautomatic ignition of the auxiliary burner from the flame of the mainburner shall not only be unimpaired by the protecting cage, but shall befacilitated thereby. v i Control of the movement of this cage is had bys mple mechanical connection from the oscillatory valve plug thereto,such connection maintaining a constant relation between the verticalposition of the cage relative to the main burner orifice and therotative position of the valve plug which determines the amount of gasdelivered to such ma n burner, and thereby the size of the main burnerflame. Y Other details of my invention and the purposes thereof willappear from the accompanying drawings and description, wherein I haveshown and described a preferred embodiment of my thermostaticallyretarded cut-off. I shall point out more specifically the new and usefulfeatures of my present invention in the appended claims.

In the drawings; Fig. 1 is a rear partially sectioned elevation of mythermostatically retarded cut-off applied to a combined illuminatingburner and valve structure such as may be used as a lighting fixture byattachment to a conventional gas-bracket or chandelier, parts beingpositioned for normal operation of the illuminating burner: Fig; 2 is anenlarged partial section through the gas-controlling valve ports taken von the plane 2-2 in Fig. 5 showingthe relative position of ports whenthe device is arranged fornormal operation of the main illuminatingburner; Fig. 3 is a view similar to Fig. 2 but showing the relativeposition of valve ports after manual actuation of the control means andbefore the auto- :matic cut-off of the main gas supply has beenaccomplished; Fig. 4: is also a view similar to Fig. 2 showing therelative position of valve ports after the automatic cutoff of the maingas supply has taken place. Fig, 5 is a plan view of the structure shownin Fig. l with parts positioned as in Fig. 7 the casing and certainother parts being cut away and the cage and burner stem omitted to moreclearly show the valve actuating mechanism; Fig. 6 is a partial frontView in elevation showing a somewhat modified form of cage; Fig; 7 is acomplete front elevation of the structure shown in Fig. l

@s eas es with casing omitted to show the valve controlling mechanism,parts being shown in a position corresponding to Fig. 3; Fig. 8 is aright elevation of the complete structure showing the position of thecage after automatic cut-oil ot the main supply has been effected.

Corresponding parts are indicated in the drawings and referred to in thefollowing description by like numerals.

In the drawings, the illuminating flame oi? the main burner appears at10, and the usual burner stem 11. The latter is mounted upon the mainvalve block 12 at he externally portion ot the An intern threadedportion id for mount- 1ire structure on a gas bracket or liltoi ipg thechandelier.

ln the valve block 12, intermediate to its t readed portions 15 1 1 andextending at right angles to 5 thereof is a tapered hole which serves asbearing for the tapered valve plug 15. This valve in the manner at anordinary gas cock is perforated midway its length by the diametricallyextending passage 16, said. passage being ar- ..lllg6(l to fall inalignment (in a certain rotative position oi the valve plug) withcorresponding passages or ports 17 and 18 leading to the threadedportion 13 and 1 respectively of the valve block.

ln longitudinal alignment with, and at a radial angle with, the passage16 and extending radially from the latter to the outer surface of thevalve plug is a smaller port 19, which, in suitable rotative position ofthe valve plug 15, registers with a small port 20 in the valve block 12,as shown clearly in Fig. 3. The port 20 leads horizontally to anauxiliary heater burner 21 contained in one of the bracket likeextensions 22, 22, of the valve block l2. The construction oi? theheater burner 21 is such as constitutes a form of Bunsen burner whereina needle valve control of the escaping is had by means of the adjustmentscrew 1n the valve block 12 on the opposite side of the valve plug l5from the auxiliary burner 21 is a lug formation through which a smallupwardly slanting aperture 25 extends trom an exterior surface of saidlug to the passage 1'? in the valve block. The outer end oi thisaperture 25 is threaded to receive am to be plugged gas-tight, by anadjustmen sc w 26. The end of this screw is arranged to lie transverseof another upwardly slanting aperture 27 extending from the passage 18in the valve block 12 to the first mentioned aperture and subste itiallyat right angles to the latter, so

that this screw is effective to control the duit tor the gas from thesource of gas supply to ti o burner stein ll (independent of control bythe valve plug 15).

vides, in general, a means for conveniently and rigidly carrying thevarious stationary mechanical parts that cooperate with the movableparts of the valve mechanism and also serves as convenient fasteningmeans for a casing which with the exception of the necessary openings"for the extrusion of operative parts, totally encloses the valvemechanism. The valve stem 30 has loosely mounted thereon a spacingcollar 2% and a double-ended, oscillatory control lever and carriesaxially external of these parts at its end, and made fast "hereto by akey screw 42, a double-extensional dog member 36* One extension 3'? oithe dog member 86 is bent baelnvardly parallel with the axis of thevalve stem and engages positively in one rotative direction with theupper edge ot' the control lever 85.

Loosely coiled about the hub of dog member 36 is a helical wire spring38 which at one end is hooked about the lower edge of control lever andat the other end engages with the extension 37 of the dog member. Aslight torsional tension in said spring maintains the control lever andthe extension 37 or the dog member normally in contact but by yielding,this spring may allow a relative rotative movement of these parts to theposition shown in Figure 7 at a certain time in the operation of thevalve. A slight axially exerted tension in said spring always maintainsthe valve plug 15 securely in its seat under uniform axial tension.

The dog member 56, has a radially extending portion diametricallyopposite the extension 37, which portion at its outer end is straddledby yoked latch member 46 pivoted thereto by a stud 47. The stud l? isfast in the extension 45 but loose in the yoked latch member e6, so thatthe latter is free to turn in one direction against the tension of aline wire spring l8, which is loosely coiled about the stud 47 and atone end tastened thereto. The other end of the spring L8 engages thelatch member 46 so normally to maintain the latter positioned against aseat provided by the very extrenr ity of the extension a5. This normalposition of the latch member 46 relative to the extension 45 is shown inFig. 7.

Lying in the path of movement of the latch member 46 is a spur-shapeddetent 52 carried by, and securely fastened to, the innor face of acurved bi-meta-llie thermostat 53. This thermostat, in the plane of itsleast dimension, conforms for the most part to the arc of a true circlesubstantially concentric with the axis of the valve )l ug, and comprisestwo conformed strips of different metals having widely differentexpansible properties such as brass and steel, made fast to each otheruniformly throughout their length, with the brass or greater expansiblemetal on the inner side.

The thermostat at one end is rigidly mounted to an extension 54: of thesupporting plate 31 by screws 55, 55, and in all other parts is free forthermally caused flexure outwardly or of a straightening nature.

A metallic heater member 56 is shown clamped in surface contact with thethermostat at the mounted end thereof and extends rearwardly, outside ofthe mechanism housing. This heater member, as clearly shown in Figs. 1,5 and 7, terminates in a hollow conically shaped hoodportion 57 having asmall opening 58, at its top and lying directly over the auxiliaryburner 21, being slightly raised therefrom.

The general position of this hood'which is wholly open at the bottom,and of the small perforation in its top, is such as to fall in verticalalignment with the auxiliary burner 21 and the main flame 10. Gas risingfrom the burner 21 is therefore collect ed by the heater hood portion 57and allowed to escape upwardly through the opening 58 in the top of samedirectly toward the flame 10. Upon ignition from the main flame, gasfrom the auxiliary will burn at the mouth thereof with a hot blue flame.This flame will play directly against the heater hood 57 which isadapted to extract heat therefrom and transmit such heat by conductionto the thermostat.

At its free end 60, the curvature of the thermostat departsfromconformation to the arc of a true circle and extends somewhat moreinwardly. Internally adjacent to and nearly in contact with thisinwardly curved extremity of the thermostat is a. loose roller 61carried by a stud which is mounted upon the supporting plate 31. A.retaining screw 63 serves to keep the roller in place. The function ofthis roller abutment is to reenforce the thermostat when the latter ismade operative to restrain the movement of the dog member 36 byengagement of spur mem ber 52 with latch member 46 as shown in Fig. 7.

To one end of the control lever 35 is directly attached a control chain65, at the other end, a latch lever 66 is pivoted at 71 for the purposeof automatically locking the control lever 35 in the position shown inFig. 7 when the control lever is made to assume this position by a pullon control chain 65.

This automatic. lockingor latching of the control lever is accomplishedby the engagement of a catch formation 67 at the end of one arm of thelever 66, witha projection 78 of the supporting plate 31, the latchlever beingnormally held in position to so engage such projection by alight wire spring 73, carried on the control lever 35 and bearing uponthe bent extremity 69 of same and upon the latch lever 66, as best shownin- Fig. 7. At the extremity of its other arm the latch lever carries acontrol chain 68, which by a pull thereon, will swing the latch lever'66to the broken line position indicated in Fig. 7. This accomplishes theunlocking of the control lever 35 and further pull on chain 68 will bepositively transmitted to the control arm, movement of which is nowpermitted.

Stops are provided to limit the movement of the control arm at eachextremity of its swing, by the extension 5a of the support plate 31 andby said projection 78.

Referringto Fig. 1 particularly, a pilot flame protecting cage orlantern chamber is shown at 82, such cage having a loosely slidablebearing 83 on the valve stem 11 and a series of elongated openings 84 inits circular side wall said openings being completely covered by acylindrical mica lining 85 extending entirely around the inside of thecage. The cage is perforated-by a circular series of small draft holes86 at its top and bottom portion for allowing the entrance of enough airto supportthe combustion of the small pilot flame shownat 87 in Fig. 8.One of these bottom draft holes is engaged by the double-fingeredterminal 88 of a crank link 89. At its opposite or lower end, this cranklink is pivoted to the end of a crank arm .90 which extends radiallyfrom the larger end of the valve plug 15 and is made fast thereto by aslotted mount? ing 91 and a retaining screw 92. Movement of the cage upand down is thus caused by the swing of the crank arm 90, with theoscillatory movement of valve-plug15.

In describing the operation of my invention, I will refer to Figs. 2, 3and l wherein the main passage 16 in valveplug 15 is shown enlarged atone end by a counterbored re cess 80, that serves to preventconstriction of the opening from passage 16 into the passage 18 in thepositionof parts shown in Fig. 3, where gas is being supplied. to boththemain burner and auxiliary or heater burner 21. I

Starting from the position of parts as in Figs. land 2 where the valveis arranged for normal supply of gas to the main burner for illuminatingpurposes and for an indefinite time, when it is desired to extinguishthe light, control chain 65 is pulled downwardly which rotates in unisonthe control lever 35 and, through the medium ofspring 38, thedog member36 until-the latter is in- 'ercepted by engagement of its latch memberas with the spur detent 52. The control lever, however, is now swungfurther against the action of spring 38 until it is automatically lockedin the position shown, in Fig. '7 as previously described. Correspondingto the position of dog member 36 in Fig. 7 the valve plug is nowpositioned as in Fig. 8, where it is clearly shown that no appreciablereduction of the gas supply to the main burner has been caused bymovement of the value plug, but where the auxiliary port 19 in the valveplug has been made to register with the auxiliary port 20 in the valveblock and where the cage 92 has been raised to the position shown inFig. 7. Gas is now supplied to the auxiliary burner 21, and, rising,ignites from the flame of the main burner which is directly above it,both main and auxiliary flames burning as shown in Fi 7.

As heat from the auxiliary flame is fed into the thermostat by theheater member 56, the former bends outwardly to the broken line positionindicated in Fig. 7, thus releasing the dog member 36 which is thereuponimpelled to its normal position, relative to the control lever 35 by thetension in spring 38. This latter movement of the dog member rotates thevalve plug 15 to the position shown in Fig. 4. Here the gas supplythrough the valve plug 15 to both main and auxiliary burners has beenshut off and the cage has been raised to the position shown in Fig. 8for protection of the small pilot flame which is left burning at themain burner orifice due to gas delivered through the by-pass aperatures25 and 27.

When it is desired to again obtain ful. light from the main burner,control chain 68 is pulled, which first disengages the latch 66 fromprojection 78 and then swings control lever 35 and thereby dog member86, by positive engagement therewith, to the position indicated bybroken lines in Fig. 7 and at the same time lowers the cage 82 to itsoriginal position as in Fig. 1. During this latter movement of the dogmember 36, the latch member as will yield when passing the spur detent52, if the latter at that time has been restored to its normal positionby cooling of the thermostat.

The parts will now remain in this position for normal operation of themain burner until the chain 65 is again pulled to extinguish the light.

The foregoing description concerns a preferredembodiment of my inventionin its simplest forms. There are, however, many additions andmodifications which could be made in the structure to serve usefulpurposes, one example of which is shown in Fi 6.

ere the cage 82 is provided with a downwardly extending curved shield 93which overhangs the heater hood 56 serving to collect and to betterguide the gas from the auxiliary burner 21 upwardly and then through theenlarged opening 9e1- in the bot tom of the cage and on upwardly throughthe cage to the main flame. More reliable ignition of gas from theauxiliary burner 21 is thereby obtained.

It will be evident that, if desired, a small pilot flame such as theflame 87 in Fig. 8 could be had by an incomplete closure of the mainvalve instead of by a constantly open by-pass conduit, or in otherwords, by an arrangement of valve ports which in the position of thevalve plug 15 in Fig. 1 would allow of a small opening from pas sage 16to passage 17 With such arrangement, however, no adjustment of the sizeof this flame would be had such as screw 26 affords in the bypassarrangement which I have illustrated in the drawings.

It will be understood that the specific structure described and depittcdherein is chosen for illustrative purposes only, and that manydepartures could be made therefrom fully within the scope of myinvention.

lVithout therefore, limiting myself to the exact embodiment disclosedwhat I claim is 1. In combination; a main gas burner and valve structureembodying automatically acting mechanism for operating the valve andincluding a separate and auxiliary gas burner positioned to beautomatically ignited from said main burner thereby to control theaction of said mechanism, and a partial closure device movable todifferent positions relative to said main burner respectively to shieldand to expose the flame thereof,said movable device being arranged andadapted to direct the flow of gas from the auxiliary to the main burner,thereby to cause ignition of the former from the latter.

2. In a gas burner and controlling valve arrangement, including a mainburner, an auxiliary burner, normally inactive and positioned below saidmain burner, to be automatically ignited by the flame of the latter whengas is delivered to such auxiliary burner, and automatic means foractuating said controlling valve embodying a controlling thermostatoperably related to said auxiliary burner, in combination; a partiallyclosed chamber structure vertically movable into and out of a positionencompassing the orifice of said main burner, and having at its bottoman opening positioned over said auxiliary burner, said chamber structurealso having an opening at its top for the escape of gas rising throughsaid chamber; and means operatively connecting said chamber with saidautomatic actuating means.

3. In a gas burner and controlling valve arrangement, including a mainburner stem, an auxiliary burner, normally inactive and gas, incombination; a partially closed chamber structure vertically slidable onsaid main burner stem into and out of a posltlon encompassing theorifice of sald stem, and having at its bottom an opening with a down-Wardly extending and outflaring lip over-' hanging said hooded portionof the heat conducting member, said chamber having an opening at the topto allow the escape of gas rising through said chamber; and means forpositively connecting said chamber structure With said movable member ofthe valve.

Signed in Boston, Massachusetts, this 22nd day of July, 1916.

, RAYMOND D. SMITH. Witnesses:

E. L. MGF'ADDEN, J E. BLAGKMAN.

